@@ -1516,8 +1516,8 @@ Common
Enable partitioned link-time optimization
fwhopr=
-Common RejectNegative UInteger Joined Var(flag_whopr)
-Enable partitioned link-time optimization with specified number of parallel jobs
+Common RejectNegative Joined Var(flag_whopr)
+Partitioned link-time optimization with number of parallel jobs or jobserver.
ftree-builtin-call-dce
Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
@@ -7556,6 +7556,13 @@ parallel using @var{n} parallel jobs by utilizing an installed
@command{make} program. The environment variable @env{MAKE} may be
used to override the program used.
+You can also specify @option{-fwhopr=jobserver} to use GNU make's
+job server mode to determine the number of parallel jobs. This
+is useful when the Makefile calling GCC is already parallel.
+The parent Makefile will need a '+' prepended to the command recipe
+for this to work. This will likely only work if @env{MAKE} is
+GNU make.
+
Disabled by default.
@item -fwpa
@@ -303,6 +303,7 @@ run_gcc (unsigned argc, char *argv[])
struct obstack env_obstack;
bool seen_o = false;
int parallel = 0;
+ int jobserver = 0;
/* Get the driver and options. */
collect_gcc = getenv ("COLLECT_GCC");
@@ -373,9 +374,17 @@ run_gcc (unsigned argc, char *argv[])
lto_mode = LTO_MODE_WHOPR;
if (option[7] == '=')
{
- parallel = atoi (option+8);
- if (parallel <= 1)
- parallel = 0;
+ if (!strcmp (option + 8, "jobserver"))
+ {
+ jobserver = 1;
+ parallel = 1;
+ }
+ else
+ {
+ parallel = atoi (option+8);
+ if (parallel <= 1)
+ parallel = 0;
+ }
}
}
else
@@ -567,23 +576,32 @@ cont:
{
struct pex_obj *pex;
char jobs[32];
+
fprintf (mstream, "all:");
for (i = 0; i < nr; ++i)
fprintf (mstream, " \\\n\t%s", output_names[i]);
fprintf (mstream, "\n");
fclose (mstream);
- /* Avoid passing --jobserver-fd= and similar flags. */
- putenv (xstrdup ("MAKEFLAGS="));
- putenv (xstrdup ("MFLAGS="));
+ if (!jobserver)
+ {
+ /* Avoid passing --jobserver-fd= and similar flags
+ unless jobserver mode is explicitely enabled.*/
+ putenv (xstrdup ("MAKEFLAGS="));
+ putenv (xstrdup ("MFLAGS="));
+ }
new_argv[0] = getenv ("MAKE");
if (!new_argv[0])
new_argv[0] = "make";
new_argv[1] = "-f";
new_argv[2] = makefile;
- snprintf (jobs, 31, "-j%d", parallel);
- new_argv[3] = jobs;
- new_argv[4] = "all";
- new_argv[5] = NULL;
+ i = 3;
+ if (!jobserver)
+ {
+ snprintf (jobs, 31, "-j%d", parallel);
+ new_argv[i++] = jobs;
+ }
+ new_argv[i++] = "all";
+ new_argv[i++] = NULL;
pex = collect_execute (CONST_CAST (char **, new_argv));
collect_wait (new_argv[0], pex);
maybe_unlink_file (makefile);
@@ -2077,7 +2077,7 @@ common_handle_option (const struct cl_decoded_option *decoded,
break;
case OPT_fwhopr:
- flag_whopr = value;
+ flag_whopr = arg;
break;
case OPT_w:
From: Andi Kleen <ak@linux.intel.com> This patch adds a new -fwhopr=jobserver mode. This is useful in parallel builds to let the submake started by lto-driver communicate with the parent make that controls the whole build to control the number of parallel jobs. Currently -fwhopr=N does not pass through the jobserver options because it cannot guarantee that the submake is GNU make. With -fwhopr=jobserver the user specifies this explicitely, so it's safe to do. Based on discussions with Richard Guenther. Passed normal boot strap and testing on x86-64 and a full LTO bootstrap with -fwhopr=jobserver and a parallel build, on x86-64-linux. v2: Fix documentation based on feedback Ok to commit? -Andi 2010-08-17 Andi Kleen <ak@linux.intel.com> * common.opt (fwhopr=): Update for -fwhopr=jobserver * doc/invoke.text (fwhopr): Document -fwhopr=jobserver. * lto-wrapper.c (run_gcc): Add jobserver mode. * opts.c (common_handle_option): Fix OPT_fwhopr for non numeric argument. --- gcc/common.opt | 4 ++-- gcc/doc/invoke.texi | 7 +++++++ gcc/lto-wrapper.c | 38 ++++++++++++++++++++++++++++---------- gcc/opts.c | 2 +- 4 files changed, 38 insertions(+), 13 deletions(-)